The nature of the agricultural problem for which the present invention constitutes a remedy has previously been discussed in the prior art. See, for example, U.S. Pat. Nos. 3,050,380; 3,135,594 and 3,533,774.
The present standard nitrification inhibitor on the market is 2-chloro-6-trichloromethyl pyridine (nitrapyrin). Because of loss by volatilization from treated fertilizers during storage, the use of this compound has tended to be restricted to applications where it can be applied simultaneously with fertilizer, for example, with anhydrous or aqueous ammonia. However, in many parts of the world, fertilizers are applied largely in the solid form, and, in such applications, it is desired to employ a nitrification inhibitor having less volatility and greater persistence.